A cache of more than 328 guns, including military style assault rifles, and 4.2 tons of ammo has been uncovered by police in Australia.

The firearms, many of which have been modified illegally, was found in a property near Monto, Queensland and is the largest weapons find in the state's history.

Among the haul were fully automatic rifles, including MP5 sub-machine guns AK-47 assault rifles as well as Glock handguns.

Shocking: Among the haul were fully automatic rifles, including MP5 sub-machine guns and AK-47 assault rifles

Some of the rifles seized were said to be worth $50,000 each, with the handguns worth $10,000 each, police said.

Detective Superintendent Jon Wacker, who led the investigation, said:'This is certainly one of the largest hauls of firearms, ammunition and weapons we have uncovered.

The weapons were seized from a property near Monto in Australia's Queensland state. Three men, believed to be a father and two sons, have been arrested in connection with the find

'While some of the weapons were determined to be registered, a significant proportion of the guns were illegal, modified or converted in some way. It is pleasing to know (the weapons) are off the street.

'(The firearms) will now be matched with a national database to see if any of the firearms have been used in other offenses.